Insulating people and things from cold temperatures involves the use of a wide variety of garments and structures designed to retain heat. For example, existing garments and structures typically use some type of passive insulation such as down feathers, wool, engineered sheets and fabrics, fiberglass insulation, and aerogel, to trap air inside the insulation. In general, the advantages of passive insulation include simplicity, low-cost, and ready availability. However, the primary drawback of using existing passive insulation is that increased insulating properties are only achieved with increased thickness. Unfortunately, thickness restrictions in some garments or structures can limit the effectiveness of passive insulation.